A newly discovered affliction has some doctors wondering if astronauts traveling to Mars could be blind by the time they got there.

A new study of astronauts shows that radiation and bone loss aren't the only health risks for long-duration stays in space. About one-third of the U.S. space station crew members return with impaired vision, a condition in which at least one case was permanent.

The data has been slow in coming since astronauts can be disqualified from flying if they have serious ailments.

"These are guys who really don't like to complain about physical issues because it may ground them. They're desire is to get back into space, so they are not complainers," neurosurgeon Bruce Ehni at Baylor College of Medicine in Houston, told Discovery News.

But in 2005, one unnamed astronaut came forward to reveal his affliction, prompting a survey of the corps. NASA discovered 35 percent of its former space station crew members, who typically spend about six months in orbit, experience visual acuity issues, agency spokesman Mike Curie told Discovery News.

"It wasn't until a couple of years ago when we started seeing this on station that we injected true acuity scans and MRIs (magnetic resonance imaging) to produce actual medical data. That type of exact data does not exist from the shuttle astronauts," who typically spent two weeks in space, Curie added.

The condition isn't serious enough to cause blindness in the short term, but it raises concern about what would happen to astronauts during a three-year mission to Mars. The vision loss seems to be due to a swelling of the optic nerve, a condition similar to a disease on Earth called pseudotumor cerebri, which mostly afflicts heavy women.

"Nobody knows why pseudotumor cerebri occurs, but it's a condition which, if left untreated in some people who are really afflicted badly with it, can lead to complete blindness," Ehni said.

"The question is 'Is there a possibility that an astronaut on a very long mission could arrive at the end of that mission unable to see, or be so visual compromised that he'd be non-functional?' The possibility is real enough that they need to look into this," Ehni said.

With a relatively small pool of subjects to study -- around 30 U.S. astronauts have lived on the International Space Station -- doctors have not been able to determine if age, gender or previous spaceflight experience affect vision loss.

Doctors believe the redistribution of cerebral spinal fluid in weightlessness is to blame, though that doesn't fully explain the situation.

"Right now we don't have enough data on this to see what is going to happen," said NASA astronaut Don Pettit, who is preparing for launch in December for his second stint aboard the space station. "Right now, I'm not concerned."

I think we will be able to get them there in a few weeks relatively soon (decades) with newer technologies being studied. Every 2 years or so, Earth and Mars get close together and that would be the ideal time for a launch of such a fast vessel.

4
posted on 09/23/2011 1:46:56 PM PDT
by GeronL
(The Right to Life came before the Right to Happiness)

Speed and propulsion are things that laymen like myself often overlook.

What really brought it home to me was watching the replay of the Apollo 11 mission online a couple years ago. Sure escape velocity is something like 17,000 mph but they don’t hold that for long. Gravity from the earth scrubbed off their speed till they slowed to fighter jet speeds before accelerating into the moon’s gravity well. Even then they needed considerable fuel for breaking into orbit around the moon.

If you could hold escape velocity for the whole trip to the moon, the moon would be a matter of hours away rather than days.

9
posted on 09/23/2011 1:58:34 PM PDT
by cripplecreek
(A vote for Amnesty is a vote for a permanent Democrat majority. ..Choose well.)

This is just another phony press release from the male astronaut’s association to try and get NASA to OK having sex in space. Have you ever met an astronaut who’d been on the space station? Hairy palms.

10
posted on 09/23/2011 2:01:26 PM PDT
by blueunicorn6
("A crack shot and a good dancer")

Thus the reason for all the gravity assist slingshot maneuvers around planets for deep space missions. The new horizons craft is hauling ass and making a bit less than one tenth of an AU per 24 hours. (currently at 21.10 AU from the sun today and 11.14 from its Pluto flyby.)

17
posted on 09/23/2011 2:12:04 PM PDT
by cripplecreek
(A vote for Amnesty is a vote for a permanent Democrat majority. ..Choose well.)

Yep. The real question is how much artificial gravity does it take to essentially eliminate all the gravity related health issues. It could be that it doesn’t take very much - but who knows... Another interesting question is what is the optimum gravity vector? I’d assume the standing position but I’ve not heard of this being a problem for people on their back stuck in bed.

I don’t think that centrifugal force is the equivalent to actual gravitational force which draws masses together with atomic force (gravitational waves?). Would it be as effective at slowing the body’s atrophy? Then there is the problem of unblocked gamma radiation - we could not lift enough lead shielding into orbit to block it. I just don’t think we are biologically able to withstand extended missions.

24
posted on 09/23/2011 3:29:50 PM PDT
by TexasRepublic
(Socialism is the gospel of envy and the religion of thieves)

I’m with you! Bring back Orion, as originally envisioned by the Freeman Dyson team. Make it clear to other nations that we intend to go forward with it and renegotiate the atmospheric test ban treaty to allow the launch of such manned behemoths.

We could easily lift all the steel shielding we could ever possibly want if only we brought back Project Orion. We could lift a ship the size of the Empire State Building, clad in 24" steel plate, with a crew of 5,000 aboard, if we wanted to. We just need the will to do it.

Once in space you could mine out a small asteroid and fly it like a ship.

I think it was John Glenn who has talked about adjusting the orbits of a half dozen asteroids and using them as a conveyor to mars for material. In fact something like that would be fine for moving people if they aren’t in a hurry.

29
posted on 09/23/2011 4:29:04 PM PDT
by cripplecreek
(A vote for Amnesty is a vote for a permanent Democrat majority. ..Choose well.)

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